The number of types of electronic devices that are commercially available has increased tremendously the past few years and the rate of introduction of new devices shows no signs of abating. Devices, such as tablet, laptop, netbook, desktop, and all-in-one computers, cell, smart, and media phones, storage devices, portable media players, navigation systems, monitors, and others, have become ubiquitous.
Power and data may be provided from one device to another over cables that may include one or more wire conductors, fiber optic cables, or other conductor. Connector inserts may be located at each end of these cables and may be inserted into connector receptacles in the communicating or power transferring devices.
Accordingly, it may be desirable for one device to be able to detect when a connection to the second device has been made. It may also be desirable to determine whether the second device is capable of providing power or needs to be powered. It may also be desirable that the first device be able to communicate with the second device. For example, the devices may need to communicate regarding which device will provide power and how much power will be provided.
At the same time, there is increasing pressure on device manufacturers to simplify these connectors and reduce pin counts in order to make them smaller and more space efficient. This reduction in pin counts may complicate efforts to provide this needed functionality.
Thus, what is needed are interface circuits that may utilize a limited number of pins to detect a presence of an accessory, determine whether the accessory can provide or receive power, communicate with the accessory regarding at least that transfer of power, and transfer power accordingly.